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ID PMID Title PublicationDate abstract
24486211 Glycyrrhizin accelerates the metabolism of triptolide through induction of CYP3A in rats. 2014 Mar 14 ETHNOPHARMACOLOGICAL RELEVANCE: Triptolide (TP), a major active component of Tripterygium wilfordii, possesses various pharmacological activities with narrow therapeutic window and severe toxicities. Glycyrrhizin (GL), the principal bioactive ingredient of licorice root extract, has been reported to be concomitantly administered with TP in treatment of rheumatoid arthritis with the aim of potentiated efficacy and reduced toxicity. The aim of the study is to investigate the effect of GL on the pharmacokinetic profiles of TP and related mechanisms. MATERIALS AND METHODS: Male and female Wistar rats were randomly divided into two groups: Control group and GL group (pretreated with GL at 100 mg/kg/day for seven consecutive days). After oral administration of TP at a single dose of 450 μg/kg, plasma concentrations of TP were determined using HPLC-MS/MS and pharmacokinetic parameters were calculated by non-compartmental analysis using Phoenix WinNonlin 6.3 software. Since CYP3A is the primary isoform of cytochrome P450s responsible for the metabolism of TP, we further determined to what extent ketoconazole (KCZ), a potent CYP3A inhibitor, could influence the effect of GL on the pharmacokinetics of TP by comparing the pharmacokinetic profiles of TP in GL group (pretreated with GL) and GL+KCZ group (pretreated with both GL and KCZ), as well as verified whether pretreatment of GL could induce the activity of hepatic CYP3A by comparing the AUC parameters after intravenous administration of midazolam (MDZ), a typical probe drug for CYP3A, in rats pretreated with vehicle or GL. RESULTS: Our study revealed marked differences in pharmacokinetic profiling patterns of TP between male and female rats in the Control group; the plasma level of TP in males was far lower than that in females. After pretreatment with GL, the pharmacokinetic profiles of TP were significantly altered in both male and female rats; a remarkable decrease was found in the value of AUC∞, MRT∞ and t1/2 in the GL group, compared with the Control group. But such a decrease was reversed by KCZ; compared with the GL group, the values of AUC∞, MRT∞ and t1/2 were significantly increased in the GL+KCZ group. Pretreatment with GL notably increased the AUC∞ of 1׳-hydroxymidazolam (OH-MDZ) and the ratio of AUC∞ of OH-MDZ to MDZ, demonstrating induction of the activity of CYP3A by GL. CONCLUSION: Pretreatment with GL significantly accelerates the metabolic elimination of TP from the body mainly through induction of hepatic CYP3A activity. These results may help explain why toxicity of TP may be attenuated with concomitant use of GL.
25730946 [The evaluation of the utility of QuantiFERON TB-Gold In-Tube; QFT-GIT]. 2014 Sep Four years has passed since QuantiFERON TB-Gold In-Tube (QFT-GIT), the third generation test, has replaced QuantiFERON-Gold in Japan. The QFT-GIT test detects interferon-gamma (IFN-γ), which is released from lymphocytes present in blood after exposure to the M. tuberculosis complex antigens ESAT-6, CFP-10 and TB7.7. These proteins are absent from all Bacille-Calmette-Guérin (BCG) strains and from most non-tuberculosis mycobacteria, resulting in fewer false positive reactions as seen with the tuberculin skin test (TST). We had various experiences with QFT-GIT during these four years. So, we discussed the usefulness and its limitation of QFT-GIT as follows: 1. Development of the principle of QuantiFERON-GIT: Nobuyuki HARADA (Research Institute of Immune Diagnosis (RIID)). QuantiFERON (QFT) was originated from diagnostic system for bovine in Australia. Although the first generation of QFT, in which PPD had been used as stimulating antigens, was approved in USA, its diagnostic value was not recognized in Japan where most of Japanese are vaccinated with BCG. By combining M. tuberculosis-specific antigens with QFT system, the second generation of QFT, QFT-Gold, was developed, and approved in Japan in 2005. QFT-Gold was soon incorporated in several guidelines such as contact investigations and nosocomial infection measures. Now, QFT-Gold was superseded by the improved QFT-Gold, the current QFT-GIT. However, since QFT-GIT may contain unstable factors including blood volume and shaking methods of blood collection tubes, development of the more improved version is strongly expected. 2. Evaluating the result of QFT-GIT in patients treated with dialysis and immunosuppressive agents: Hidetoshi IGARI (National Hospital Organization Chiba-East National Hospital) The effectiveness of QuantiFERON TB-Gold In-Tube was analyzed in the patients with chronic kidney disease (CKD) and rheumatoid arthritis (RA). QFT positive was 7% and 11% respectively, and indeterminate was 5% and 2% respectively. QFT positive was 2% in hemodialysis patients, significantly lower than that of CKD. QFT positive after biological drug was administered was 8% in RA patients, significantly lower than 15% of RA without biological drug. The rate of latent tuberculosis patients in CKD was as well as health care workers (HCWs) of 8% of QFT positive. On the other hand that of RA might be higher than HCWs. Hemodialysis and biological drug administration might attenuate QFT result with lower rate of positive. The rate of indeterminate was less than 5%. This results was improved in compared with former generation QFT. 3. QFT in Vietnam: Naoto KEICHO (Research Institute of Tuberculosis, JATA). We have promoted collaborative research on tuberculosis with Vietnamese institutes since 2002. NCGM-BMH Medical Collaboration Center plays an important role in the clinical research projects. We report 1) quality assessment of QFT for tuberculosis infection, 2) prevalence and risk factors for tuberculosis infection among hospital workers, and 3) analysis of factors lowering sensitivity of QFT for active tuberculosis. We also discuss significance of QFT in developing countries. 4. Comparison of diagnostic performances using QFT Gold and Gold In-Tube in patients with active tuberculosis: Tetsuya YAGI (Department of Infectious Diseases, Center of National University Hospital for Infection Control, Nagoya University Hospital). The goal of this study was to assess the diagnostic performances of QFT-GIT compared with QFT-Gold in patients with active tuberculosis in Nagoya University Hospital, in Japan. The sensitivity of QFT-Gold was 87.2%, the specificity of that was 77.5%. The sensitivity of QFT-GIT was 88.8%, specificity 73.2%. The performance of QFT-GIT was the same as that of QFT-Gold. The QFT-GIT tended to show higher concentration values of IFN-γ than that of QFT-Gold especially in patients with extra pulmonary tuberculosis, smear positive pulmonary tuberculosis, both lung lesion and using immunosuppressive medications. 5. Simultaneous and longitudinal comparison between QFT Gold and Gold In-Tube among health care workers; Tomoshige MATSUMOTO (Department of Clinical Laboratory Medicine, Osaka Anti-Tuberculosis Association Osaka Hospital. ex-Osaka Prefectural Medical Center for Respiratory and Allergic Diseases). The aim of this study was to compare the indeterminate rates between QFT-GIT and QFT-Gold tests. And to make longitudinal comparison by QFT-Gold assay to the same HCW. We collected blood samples by simultaneously QFT-Gold and QFT-GIT from 120 staff members in the institute who participated in this prospective comparison study. Moreover, the latest QFT-Gold test was longitudinally compared for the same 55 staff members who have received QFT-Gold before. The statistically significant difference was observed in the results of indeterminate rate between QFT-Gold and QFT-GIT using the same blood samples. It is concluded that QFT-Gold and QFT-GIT are different assays therefore it is difficult to compare QFT-Gold with QFT-GIT data on the same level. Concerning the follow-up test of the 55 people by QFT-Gold, 5 turned from positive to negative and 4 turned from indeterminate to negative. From this analysis, QFT-Gold positive subjects in the previous time have not been always positive. 6. Interpreting QFT "equivocal" results: Kenji MATSUMOTO (Osaka City Public Health Office). The participants were examined QFT-GIT test after two months to four months from last contact of smear-positive tuberculosis cases in contact investigations. We enrolled 79 contacts whose tests of QFT-GIT were equivocal results. The second QFT-GIT results were 42 negative (53.2%), 28 equivocal (35.4%) and nine positive (11.4%). 64% of the second QFT-GIT tests result in negative or positive among the first QFT-GIT equivocal contacts. When the second QFT-GIT tests were positive, it is highly probable that the contacts were infected tuberculosis and we adequately could treat latent tuberculosis infected contacts.
25486901 In silico analysis of autoimmune diseases and genetic relationships to vaccination against 2014 Dec 9 BACKGROUND: Near universal administration of vaccines mandates intense pharmacovigilance for vaccine safety and a stringently low tolerance for adverse events. Reports of autoimmune diseases (AID) following vaccination have been challenging to evaluate given the high rates of vaccination, background incidence of autoimmunity, and low incidence and variable times for onset of AID after vaccinations. In order to identify biologically plausible pathways to adverse autoimmune events of vaccine-related AID, we used a systems biology approach to create a matrix of innate and adaptive immune mechanisms active in specific diseases, responses to vaccine antigens, adjuvants, preservatives and stabilizers, for the most common vaccine-associated AID found in the Vaccine Adverse Event Reporting System. RESULTS: This report focuses on Guillain-Barre Syndrome (GBS), Rheumatoid Arthritis (RA), Systemic Lupus Erythematosus (SLE), and Idiopathic (or immune) Thrombocytopenic Purpura (ITP). Multiple curated databases and automated text mining of PubMed literature identified 667 genes associated with RA, 448 with SLE, 49 with ITP and 73 with GBS. While all data sources provided valuable and unique gene associations, text mining using natural language processing (NLP) algorithms provided the most information but required curation to remove incorrect associations. Six genes were associated with all four AIDs. Thirty-three pathways were shared by the four AIDs. Classification of genes into twelve immune system related categories identified more "Th17 T-cell subtype" genes in RA than the other AIDs, and more "Chemokine plus Receptors" genes associated with RA than SLE. Gene networks were visualized and clustered into interconnected modules with specific gene clusters for each AID, including one in RA with ten C-X-C motif chemokines. The intersection of genes associated with GBS, GBS peptide auto-antigens, influenza A infection, and influenza vaccination created a subnetwork of genes that inferred a possible role for the MAPK signaling pathway in influenza vaccine related GBS. CONCLUSIONS: Results showing unique and common gene sets, pathways, immune system categories and functional clusters of genes in four autoimmune diseases suggest it is possible to develop molecular classifications of autoimmune and inflammatory events. Combining this information with cellular and other disease responses should greatly aid in the assessment of potential immune-mediated adverse events following vaccination.
23700638 Polyethylene glycol–coated gold nanoshells conjugated with anti-VCAM-1 antibody. 2004 Optical fluorescence imaging is increasingly used to monitor biological functions of specific targets in small animals (1-3). However, the intrinsic fluorescence of biomolecules poses a problem when fluorophores that absorb visible light (350–650 nm) are used. Near-infrared (NIR) fluorescence (650–1,000 nm) detection avoids the background fluorescence interference of natural biomolecules, providing a high contrast between target and background tissues. NIR fluorophores have a wider dynamic range and minimal background as a result of reduced scattering compared with visible fluorescence detection. They also have high sensitivity, resulting from low infrared background, and high extinction coefficients, which provide high quantum yields. The NIR region is also compatible with solid-state optical components, such as diode lasers and silicon detectors. NIR fluorescence imaging is becoming a noninvasive alternative to radionuclide imaging in small animals (4, 5). Photoacoustic imaging (PAI) is an emerging hybrid biomedical imaging modality based on photoacoustic effects (6-9). In PAI, non-ionizing optical pulses are delivered into biological tissues. Some of the delivered energy is absorbed and converted into heat, leading to transient thermoelastic expansion and thus ultrasonic emission. The generated ultrasonic waves are then detected by ultrasonic transducers to form images. It is known that optical absorption is closely associated with physiological properties, such as hemoglobin concentration and oxygen saturation. As a result, the magnitude of the ultrasonic emission (i.e., photoacoustic signal), which is proportional to the local energy deposition, reveals physiologically specific optical absorption contrast and tissue structures. However, exogenous NIR contrast agents are necessary to overcome the intrinsic low tissue and hemoglobin absorption and the scattering of signal in tissue. On the other hand, these small molecules exhibit fast clearance, small optical absorption cross section, and non-targeted specificity. Therefore, there is a need for contrast agents with long blood circulation and targeted specificity. Gold (Au) nanoparticles have been studied as molecular imaging agents because of their bright NIR fluorescence emission of 700–900 nm and low toxicity (10). They can be tuned to emit in a range of wavelengths by changing their sizes, shapes, and composition, thus providing broad excitation profiles and high absorption coefficients. They can be coated and capped with hydrophilic materials for additional conjugation with biomolecules, such as peptides, antibodies, nucleic acids, and small organic compounds for in vitro and in vivo studies. Use of Au nanoparticles has been approved by the United States Food and Drug Administration for the treatment of patients with rheumatoid arthritis. Au nanoparticles have been studied as contrast agents in X-ray/computed tomography, NIR optical coherence tomography, PAI, and photoacoustic tomography (PAT) (3). NIR Au nanocages (AuNCs) are biocompatible, have low toxicity, and are tunable to strong NIR absorption (11). They have an outer edge of ~50 nm and an inner edge of ~42 nm, with a wall thickness of ~4 nm. Yang et al. (12) performed PAT of the cerebral cortex of rats with polyethylene glycol–coated AuNCs (PEG-AuNCs) as an optical contrast agent. The investigators observed an enhanced optical contrast in the vasculature in the cerebral cortex. Song et al. (13) demonstrated the use of Au nanocages as a PAI probe for detection of sentinel lymph nodes in rats. Endothelial cells are important cells in inflammatory responses (14, 15). Bacterial lipopolysaccharide, virus, inflammation, and tissue injury increase tumor necrosis factor α (TNFα), interleukin-1 (IL-1), and other cytokine and chemokine secretion. Emigration of leukocytes from blood is dependent on their ability to adhere to endothelial cell surfaces. Inflammatory mediators and cytokines induce chemokine secretion from endothelial cells and other vascular cells and increase their expression of cell surface adhesion molecules, such as intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), integrins, and selectins. Chemokines are chemotactic toward leukocytes and toward sites of inflammation and tissue injury. The movement of leukocytes through endothelial junctions into the extravascular space are highly orchestrated through various interactions with different adhesion molecules on endothelial cells (16). VCAM-1 is found in very low levels on the cell surface of resting endothelial cells and other vascular cells, such as smooth muscle cells and fibroblasts (16-20). VCAM-1 binds to the very late antigen-4 (VLA-4) integrin on the cell surface of leukocytes. IL-1 and TNFα increase expression of VCAM-1 and other cell adhesion molecules on the vascular endothelial cells, which leads to leukocyte adhesion to the activated endothelium. Furthermore, VCAM-1 expression is also induced by oxidized low-density lipoproteins under atherogenic conditions (21). Overexpression of VCAM-1 by atherosclerotic lesions plays an important role in their progression to vulnerable plaques, which may erode and rupture. Rouleau et al. (22) developed gold nanoshells coated with polyethylene glycol (PEG) and anti-VCAM-1 antibody (AuNS-PEG-VCAM-1Ab) for use with in vivo PAT imaging of atherosclerotic plaques in mice.
25491030 Pulmonary nocardiosis caused by Nocardia cyriacigeorgica in patients with Mycobacterium av 2014 Dec 10 BACKGROUND: Pulmonary nocardiosis frequently occurs in immunocompromised hosts and in some immunocompetent hosts with chronic lung disease; however, few reports have described pulmonary nocardiosis with nontuberculous mycobacterial lung infection. Here we report for the first time two cases of pulmonary nocardiosis caused by Nocardia cyriacigeorgica associated with Mycobacterium avium complex (MAC) lung disease caused by M. avium. CASE PRESENTATION: Case 1 is that of a 72-year-old Japanese man with untreated MAC lung disease, who was diagnosed with rheumatoid arthritis and initiated on methotrexate. After 3 years of methotrexate therapy, the patient remained smear-negative and culture-positive for MAC, but also became smear-positive for Nocardia species. He received trimethoprim/sulfamethoxazole, and his symptoms and lung infiltrates improved. Case 2 is that of an immunocompetent 53-year-old Japanese woman with MAC lung disease, who was treated with a combined therapy of clarithromycin, rifampicin, ethambutol, and levofloxacin. MAC sputum culture was negative after 1 year of combined treatment, which was maintained for 2 years. After four treatment-free years, Nocardia species were occasionally isolated from her sputum, although MAC was rarely isolated from sputum cultures over the same period. In both cases, the Nocardia species were identified as the recently defined N. cyriacigeorgica by 16S ribosomal RNA gene sequencing. CONCLUSION: We report two cases of pulmonary nocardiosis caused by N. cyriacigeorgica associated with MAC lung disease caused by M. avium and suggest that N. cyriacigeorgica may be a major infective agent associated with MAC lung disease.
25025429 Single nucleotide polymorphisms with cis-regulatory effects on long non-coding transcripts 2014 We applied genome-wide allele-specific expression analysis of monocytes from 188 samples. Monocytes were purified from white blood cells of healthy blood donors to detect cis-acting genetic variation that regulates the expression of long non-coding RNAs. We analysed 8929 regions harboring genes for potential long non-coding RNA that were retrieved from data from the ENCODE project. Of these regions, 60% were annotated as intergenic, which implies that they do not overlap with protein-coding genes. Focusing on the intergenic regions, and using stringent analysis of the allele-specific expression data, we detected robust cis-regulatory SNPs in 258 out of 489 informative intergenic regions included in the analysis. The cis-regulatory SNPs that were significantly associated with allele-specific expression of long non-coding RNAs were enriched to enhancer regions marked for active or bivalent, poised chromatin by histone modifications. Out of the lncRNA regions regulated by cis-acting regulatory SNPs, 20% (n = 52) were co-regulated with the closest protein coding gene. We compared the identified cis-regulatory SNPs with those in the catalog of SNPs identified by genome-wide association studies of human diseases and traits. This comparison identified 32 SNPs in loci from genome-wide association studies that displayed a strong association signal with allele-specific expression of non-coding RNAs in monocytes, with p-values ranging from 6.7×10(-7) to 9.5×10(-89). The identified cis-regulatory SNPs are associated with diseases of the immune system, like multiple sclerosis and rheumatoid arthritis.
24944284 n-3 PUFAs reduce T-helper 17 cell differentiation by decreasing responsiveness to interleu 2014 Aug Cluster of differentiation 4(+) (CD4(+)) effector T-cell subsets [e.g., T-helper (Th) 1 and Th17] are implicated in autoimmune and inflammatory disorders such as multiple sclerosis, psoriasis, and rheumatoid arthritis. Interleukin (IL)-6 is a pleiotropic cytokine that induces Th17 polarization via signaling through the membrane-bound transducer glycoprotein 130 (GP130). Previously, we demonstrated that n-3 (ω-3) polyunsaturated fatty acids (PUFAs) reduce CD4(+) T-cell activation and differentiation into pathogenic Th17 cells by 25-30%. Here we report that n-3 PUFAs alter the response of CD4(+) T cells to IL-6 in a lipid raft membrane-dependent manner. Naive splenic CD4(+) T cells from fat-1 transgenic mice exhibited 30% lower surface expression of the IL-6 receptor. This membrane-bound receptor is known to be shed during cellular activation, but the release of soluble IL-6 receptor after treatment with anti-CD3 and anti-CD28 was not changed in the CD4(+) T cells from fat-1 mice, suggesting that the decrease in surface expression was not due to ectodomain release. We observed a significant 20% decrease in the association of GP130 with lipid rafts in activated fat-1 CD4(+) T cells and a 35% reduction in GP130 homodimerization, an obligate requirement for downstream signaling. The phosphorylation of signal transducer and activator of transcription 3 (STAT3), a downstream target of IL-6-dependent signaling, was also decreased by 30% in response to exogenous IL-6 in fat-1 CD4(+) T cells. Our results suggest that n-3 PUFAs suppress Th17 cell differentiation in part by reducing membrane raft-dependent responsiveness to IL-6, an essential polarizing cytokine.
24699061 Evaluation of antidepressant properties of the p38 MAP kinase inhibitor losmapimod (GW8565 2014 Jun Pro-inflammatory cytokines (PICs) may play important pathophysiological roles in some forms of Major Depressive Disorder (MDD). The p38 MAPK inhibitor losmapimod (GW856553) attenuates the pro-inflammatory response in humans by reducing PIC production. Losmapimod (7.5 mg BD) was administered for 6 weeks in two randomised, placebo-controlled trials in subjects with MDD enriched with symptoms of loss of energy/interest and psychomotor retardation (Studies 574 and 009). Primary efficacy endpoints were the Bech 6-item depression subscale of the HAMD-17 (the 'Bech,') for Study 009; and the Bech, Inventory of Depressive Symptomatology-Clinician Rated (IDS-C), HAMD-17, and Quick Inventory of Depressive Symptomatology (self-rated) (QIDS-SR) for Study 574. Key cytokine biomarker levels were also measured. Study 574 (n=24) was terminated prematurely in light of emerging data from an internal study in rheumatoid arthritis. Efficacy results available at termination favoured losmapimod (Bech, 6 weeks: endpoint drug vs. placebo difference = -4.10; 95% CI, -7.36, -0.83; p=0.017). A subsequent study, Study 009 (n=128), designed using a Bayesian approach based on a prior derived from Study 574, showed no advantage for losmapimod (Bech, 6 weeks: endpoint drug vs. placebo difference = 1.11; 95% credible interval, -0.22, 2.50). Biomarker data showed no significant changes. In conclusion 7.5 mg BID losmapimod was not effective in MDD.
23771435 Prenatal nitrate intake from drinking water and selected birth defects in offspring of par 2013 Sep BACKGROUND: Previous studies of prenatal exposure to drinking-water nitrate and birth defects in offspring have not accounted for water consumption patterns or potential interaction with nitrosatable drugs. OBJECTIVES: We examined the relation between prenatal exposure to drinking-water nitrate and selected birth defects, accounting for maternal water consumption patterns and nitrosatable drug exposure. METHODS: With data from the National Birth Defects Prevention Study, we linked addresses of 3,300 case mothers and 1,121 control mothers from the Iowa and Texas sites to public water supplies and respective nitrate measurements. We assigned nitrate levels for bottled water from collection of representative samples and standard laboratory testing. Daily nitrate consumption was estimated from self-reported water consumption at home and work. RESULTS: With the lowest tertile of nitrate intake around conception as the referent group, mothers of babies with spina bifida were 2.0 times more likely (95% CI: 1.3, 3.2) to ingest ≥ 5 mg nitrate daily from drinking water (vs. < 0.91 mg) than control mothers. During 1 month preconception through the first trimester, mothers of limb deficiency, cleft palate, and cleft lip cases were, respectively, 1.8 (95% CI: 1.1, 3.1), 1.9 (95% CI: 1.2, 3.1), and 1.8 (95% CI: 1.1, 3.1) times more likely than control mothers to ingest ≥ 5.42 mg of nitrate daily (vs. < 1.0 mg). Higher water nitrate intake did not increase associations between prenatal nitrosatable drug use and birth defects. CONCLUSIONS: Higher water nitrate intake was associated with several birth defects in offspring, but did not strengthen associations between nitrosatable drugs and birth defects.
25555357 Lignans and aromatic glycosides from Piper wallichii and their antithrombotic activities. 2015 Mar 13 ETHNOPHARMACOLOGICAL RELEVANCE: Piper wallichii (Miq.) Hand.-Mazz. is a medicinal plant used widely for the treatment of rheumatoid arthritis, inflammatory diseases, cerebral infarction and angina in China. Previous study showed that lignans and neolignans from Piper spp. had potential inhibitory activities on platelet aggregation. In the present study, we investigated the chemical constituents of Piper wallichii and their antithrombotic activities, to support its traditional uses. MATERIALS AND METHODS: The methanolic extract of the air-dried stems of Piper wallichii was separated and purified using various chromatographic methods, including semi-preparative HPLC. The chemical structures of the isolates were determined by detailed spectroscopic analysis, and acidic hydrolysis in case of the new glycoside 2. Determination of absolute configurations of the new compound 1 was facilitated by calculated electronic circular dichroism using time-dependent density-functional theory. All compounds were tested for their inhibitory effects on platelet aggregation induced by platelet activating factor (PAF) in rabbits׳ blood model, from which the active ones were further evaluated the in vivo antithrombotic activity in zebrafish model. RESULTS: A new neolignan, piperwalliol A (1), and four new aromatic glycosides, piperwalliosides A-D (2-5) were isolated from the stems of Piper wallichii, along with 25 known compounds, including 13 lignans, six aromatic glycosides, two phenylpropyl aldehydes, and four biphenyls. Five known compounds (6-10) showed in vitro antiplatelet aggregation activities. Among them, (-)-syringaresinol (6) was the most active compound with an IC50 value of 0.52 mM. It is noted that in zebrafish model, the known lignan 6 showed good in vivo antithrombotic effect with a value of 37% at a concentration of 30 μM, compared with the positive control aspirin with the inhibitory value of 74% at a concentration of 125μM. CONCLUSION: This study demonstrated that lignans, phenylpropanoid and biphenyl found in Piper wallichii may be responsible for antithrombotic effect of the titled plant.
25461443 Importance of Toll-like receptors for B lymphocyte survival in primary Sjögren's syndrome 2013 Jul 10 The Sjögren's syndrome is a systemic autoimmune disease characterized by lymphocytic infiltration of the glands responsible for mouth and eyes dryness. A minority of infiltrating B cells is organized as germinal centers while the majority is aggregated into clusters of transitional and marginal zone B cells. The Toll-like receptor 9 (TLR9) recognizes microbial DNA but also, sometimes, the self DNA. It appears to be a key determinant of the survival and differentiation of B lymphocytes. After laser micro-dissection of B cells from salivary glands, analyses by quantitative RT-PCR showed that transitional B cells express high level of TLR9 mRNA unlike B cells from germinal centers. B lymphocytes from healthy donors were sorted by flow cytometry and stimulated in vitro with their TLR9. It induces survival, activation and proliferation associated with phenotypic changes. Transitional B cells exhibited characteristics of the marginal zone, whereas mature B cells expressed follicular germinal center specificities. Finally, IgM and IgG were secreted by both population, but with elevated production of autoantibodies by the transitional B cells. Increased expression of TLR9 by transitional B cells suggests that they may be highly sensitive to differentiate into autoantibody secreting cells through maturation into the marginal zone into the salivary glands. TLR9 might be a target for forthcoming biotherapies.
23647065 Activation of adenosine A(2A) receptor reduces osteoclast formation via PKA- and ERK1/2-me 2013 Jul BACKGROUND AND PURPOSE: We previously reported that adenosine, acting at adenosine A(2A) receptors (A(2A)R), inhibits osteoclast (OC) differentiation in vitro (A(2A)R activation OC formation reduces by half) and in vivo. For a better understanding how adenosine A(2A)R stimulation regulates OC differentiation, we dissected the signalling pathways involved in A(2A)R signalling. EXPERIMENTAL APPROACH: OC differentiation was studied as TRAP+ multinucleated cells following M-CSF/RANKL stimulation of either primary murine bone marrow cells or the murine macrophage line, RAW264.7, in presence/absence of the A(2A)R agonist CGS21680, the A(2A)R antagonist ZM241385, PKA activators (8-Cl-cAMP 100 nM, 6-Bnz-cAMP) and the PKA inhibitor (PKI). cAMP was quantitated by EIA and PKA activity assays were carried out. Signalling events were studied in PKA knockdown (lentiviral shRNA for PKA) RAW264.7 cells (scrambled shRNA as control). OC marker expression was studied by RT-PCR. KEY RESULTS: A(2A)R stimulation increased cAMP and PKA activity which and were reversed by addition of ZM241385. The direct PKA stimuli 8-Cl-cAMP and 6-Bnz-cAMP inhibited OC maturation whereas PKI increased OC differentiation. A(2A)R stimulation inhibited p50/p105 NFκB nuclear translocation in control but not in PKA KO cells. A(2A)R stimulation activated ERK1/2 by a PKA-dependent mechanism, an effect reversed by ZM241385, but not p38 and JNK activation. A(2A)R stimulation inhibited OC expression of differentiation markers by a PKA-mechanism. CONCLUSIONS AND IMPLICATIONS: A(2A)R activation inhibits OC differentiation and regulates bone turnover via PKA-dependent inhibition of NFκB nuclear translocation, suggesting a mechanism by which adenosine could target bone destruction in inflammatory diseases like rheumatoid arthritis.
23593036 Functional IL6R 358Ala allele impairs classical IL-6 receptor signaling and influences ris 2013 Apr Inflammation, which is directly regulated by interleukin-6 (IL-6) signaling, is implicated in the etiology of several chronic diseases. Although a common, non-synonymous variant in the IL-6 receptor gene (IL6R Asp358Ala; rs2228145 A>C) is associated with the risk of several common diseases, with the 358Ala allele conferring protection from coronary heart disease (CHD), rheumatoid arthritis (RA), atrial fibrillation (AF), abdominal aortic aneurysm (AAA), and increased susceptibility to asthma, the variant's effect on IL-6 signaling is not known. Here we provide evidence for the association of this non-synonymous variant with the risk of type 1 diabetes (T1D) in two independent populations and confirm that rs2228145 is the major determinant of the concentration of circulating soluble IL-6R (sIL-6R) levels (34.6% increase in sIL-6R per copy of the minor allele 358Ala; rs2228145 [C]). To further investigate the molecular mechanism of this variant, we analyzed expression of IL-6R in peripheral blood mononuclear cells (PBMCs) in 128 volunteers from the Cambridge BioResource. We demonstrate that, although 358Ala increases transcription of the soluble IL6R isoform (P = 8.3×10⁻²²) and not the membrane-bound isoform, 358Ala reduces surface expression of IL-6R on CD4+ T cells and monocytes (up to 28% reduction per allele; P≤5.6×10⁻²²). Importantly, reduced expression of membrane-bound IL-6R resulted in impaired IL-6 responsiveness, as measured by decreased phosphorylation of the transcription factors STAT3 and STAT1 following stimulation with IL-6 (P≤5.2×10⁻⁷). Our findings elucidate the regulation of IL-6 signaling by IL-6R, which is causally relevant to several complex diseases, identify mechanisms for new approaches to target the IL-6/IL-6R axis, and anticipate differences in treatment response to IL-6 therapies based on this common IL6R variant.
24498279 Autoimmunity-associated LYP-W620 does not impair thymic negative selection of autoreactive 2014 A C1858T (R620W) variation in the PTPN22 gene encoding the tyrosine phosphatase LYP is a major risk factor for human autoimmunity. LYP is a known negative regulator of signaling through the T cell receptor (TCR), and murine Ptpn22 plays a role in thymic selection. However, the mechanism of action of the R620W variant in autoimmunity remains unclear. One model holds that LYP-W620 is a gain-of-function phosphatase that causes alterations in thymic negative selection and/or thymic output of regulatory T cells (Treg) through inhibition of thymic TCR signaling. To test this model, we generated mice in which the human LYP-W620 variant or its phosphatase-inactive mutant are expressed in developing thymocytes under control of the proximal Lck promoter. We found that LYP-W620 expression results in diminished thymocyte TCR signaling, thus modeling a "gain-of-function" of LYP at the signaling level. However, LYP-W620 transgenic mice display no alterations of thymic negative selection and no anomalies in thymic output of CD4(+)Foxp3(+) Treg were detected in these mice. Lck promoter-directed expression of the human transgene also causes no alteration in thymic repertoire or increase in disease severity in a model of rheumatoid arthritis, which depends on skewed thymic selection of CD4(+) T cells. Our data suggest that a gain-of-function of LYP is unlikely to increase risk of autoimmunity through alterations of thymic selection and that LYP likely acts in the periphery perhaps selectively in regulatory T cells or in another cell type to increase risk of autoimmunity.
24576620 T cell epitope mimicry between Sjögren's syndrome Antigen A (SSA)/Ro60 and oral, gut, ski 2014 May This study was undertaken to test the hypothesis that Sjogren's syndrome Antigen A (SSA)/Ro60-reactive T cells are activated by peptides originating from oral and gut bacteria. T cell hybridomas generated from HLA-DR3 transgenic mice recognized 3 regions on Ro60, with core epitopes mapped to amino acids 228-238, 246-256 and 371-381. BLAST analysis identified several mimicry peptides, originating from human oral, intestinal, skin and vaginal bacteria, as well as environmental bacteria. Amongst these, a peptide from the von Willebrand factor type A domain protein (vWFA) from the oral microbe Capnocytophaga ochracea was the most potent activator. Further, Ro60-reactive T cells were activated by recombinant vWFA protein and whole Escherichia coli expressing this protein. These results demonstrate that peptides derived from normal human microbiota can activate Ro60-reactive T cells. Thus, immune responses to commensal microbiota and opportunistic pathogens should be explored as potential triggers for initiating autoimmunity in SLE and Sjögren's syndrome.
22956128 Fermentation of sugars and sugar alcohols by plaque Lactobacillus strains. 2013 Jul OBJECTIVE: The objective was to analyse the ability of Lactobacillus strains isolated from supragingival plaque of subjects with hyposalivation and from healthy controls to ferment sugars and sugar alcohols. MATERIAL AND METHODS: Fifty strains isolated from interproximal plaque from subjects with radiation-induced hyposalivation (25 strains), subjects with primary Sjögren's syndrome (16 strains) and from subjects with normal salivary secretion rate (9 strains) were tested. Growth and pH were determined after 24 and 48 h of anaerobic incubation in vials containing basal media with 1 % of glucose, fructose, sucrose, mannitol, sorbitol or xylitol. RESULTS: No differences between strains isolated from hyposalivated subjects and controls were detected. All strains lowered the pH to <5.0 from fructose and the majority of the strains from glucose and sucrose. A pH of <5.5 was seen for 52 % of the strains using mannitol, 50 % using sorbitol and 36 % using xylitol. The ability to produce acids from sugars and sugar alcohols was highest among strains of Lactobacillus rhamnosus, Lactobacillus casei and Lactobacillus paracasei and lowest among Lactobacillus fermentum strains. CONCLUSION: A large number of Lactobacillus strains are able to ferment not only sugars but also the sugar substitutes mannitol, sorbitol and xylitol to pH levels critical for enamel demineralisation. CLINICAL RELEVANCE: Our findings suggest that products containing mannitol, sorbitol and/or xylitol may contribute to the acidogenic potential of the dental plaque and especially in hyposalivated subjects with high numbers of lactobacilli.
25379019 Inhibition of p70 S6 kinase (S6K1) activity by A77 1726 and its effect on cell proliferati 2014 Oct Leflunomide is a novel immunomodulatory drug prescribed for treating rheumatoid arthritis. It inhibits the activity of protein tyrosine kinases and dihydroorotate dehydrogenase, a rate-limiting enzyme in the pyrimidine nucleotide synthesis pathway. Here, we report that A77 1726, the active metabolite of leflunomide, inhibited the phosphorylation of ribosomal protein S6 and two other substrates of S6K1, insulin receptor substrate-1 and carbamoyl phosphate synthetase 2, in an A375 melanoma cell line. A77 1726 increased the phosphorylation of AKT, p70 S6 (S6K1), ERK1/2, and MEK through the feedback activation of the IGF-1 receptor-mediated signaling pathway. In vitro kinase assay revealed that leflunomide and A77 1726 inhibited S6K1 activity with IC50 values of approximately 55 and 80 μM, respectively. Exogenous uridine partially blocked A77 1726-induced inhibition of A375 cell proliferation. S6K1 knockdown led to the inhibition of A375 cell proliferation but did not potentiate the antiproliferative effect of A77 1726. A77 1726 stimulated bromodeoxyuridine incorporation in A375 cells but arrested the cell cycle in the S phase, which was reversed by addition of exogenous uridine or by MAP kinase pathway inhibitors but not by rapamycin and LY294002 (a phosphoinositide 3-kinase inhibitor). These observations suggest that A77 1726 accelerates cell cycle entry into the S phase through MAP kinase activation and that pyrimidine nucleotide depletion halts the completion of the cell cycle. Our study identified a novel molecular target of A77 1726 and showed that the inhibition of S6K1 activity was in part responsible for its antiproliferative activity. Our study also provides a novel mechanistic insight into A77 1726-induced cell cycle arrest in the S phase.
23741300 The triterpenoid CDDO-Me inhibits bleomycin-induced lung inflammation and fibrosis. 2013 Pulmonary Fibrosis (PF) is a devastating progressive disease in which normal lung structure and function is compromised by scarring. Lung fibrosis can be caused by thoracic radiation, injury from chemotherapy and systemic diseases such as rheumatoid arthritis that involve inflammatory responses. CDDO-Me (Methyl 2-cyano-3,12-dioxooleana-1,9(11)dien-28-oate, Bardoxolone methyl) is a novel triterpenoid with anti-fibrotic and anti-inflammatory properties as shown by our in vitro studies. Based on this evidence, we hypothesized that CDDO-Me would reduce lung inflammation, fibrosis and lung function impairment in a bleomycin model of lung injury and fibrosis. To test this hypothesis, mice received bleomycin via oropharyngeal aspiration (OA) on day zero and CDDO-Me during the inflammatory phase from days -1 to 9 every other day. Bronchoalveolar lavage fluid (BALF) and lung tissue were harvested on day 7 to evaluate inflammation, while fibrosis and lung function were evaluated on day 21. On day 7, CDDO-Me reduced total BALF protein by 50%, alveolar macrophage infiltration by 40%, neutrophil infiltration by 90% (p≤0.01), inhibited production of the inflammatory cytokines KC and IL-6 by over 90% (p≤0.001), and excess production of the pro-fibrotic cytokine TGFβ by 50%. CDDO-Me also inhibited α-smooth muscle actin and fibronectin mRNA by 50% (p≤0.05). On day 21, CDDO-Me treatment reduced histological fibrosis, collagen deposition and αSMA production. Lung function was significantly improved at day 21 by treatment with CDDO-Me, as demonstrated by respiratory rate and dynamic compliance. These new findings reveal that CDDO-Me exhibits potent anti-fibrotic and anti-inflammatory properties in vivo. CDDO-Me is a potential new class of drugs to arrest inflammation and ameliorate fibrosis in patients who are predisposed to lung injury and fibrosis incited by cancer treatments (e.g. chemotherapy and radiation) and by systemic autoimmune diseases.
24504816 CD21(-/low) marginal zone B cells highly express Fc receptor-like 5 protein and are killed 2014 Feb OBJECTIVE: Hepatitis C virus (HCV) is associated with B cell lymphoproliferative disorders, including mixed cryoglobulinemia (MC) vasculitis and B cell non-Hodgkin's lymphoma. The expansion of clonal and autoreactive rheumatoid factor-bearing CD21(-/low) marginal zone (MZ) B cells was demonstrated in patients with HCV-associated MC vasculitis. Fc receptor-like (FCRL) proteins comprise a family of immunoregulatory proteins preferentially expressed on B lineage cells. The goal of this study was to investigate the expression of FCRL proteins 1-5 on B cells from patients with HCV-associated MC vasculitis. METHODS: Expression of FCRL proteins 1-5 was assessed by flow cytometry on B cells from 15 HCV-infected patients with type II MC (7 of whom had B cell non-Hodgkin's lymphoma), 20 HCV-infected patients without MC, and 20 healthy donors. To evaluate FCRL-5 as an immunotherapy target in HCV-associated MC vasculitis, 2 anti-FCRL-5 recombinant immunotoxins were produced using anti-FCRL-5 monoclonal antibodies and Pseudomonas exotoxin. RESULTS: Expression of FCRLs 2, 3, and 5 was markedly increased while expression of FCRL-1 was decreased on clonal CD21(-/low) MZ B cells, as compared with other B cell subsets, from HCV-infected patients and healthy donors. However, there was no difference in the pattern of FCRL expression between HCV-MC patients with lymphoma and those without lymphoma. The anti-FCRL-5 immunotoxins showed specific cytotoxicity against FCRL-5-expressing clonal CD21(-/low) MZ B cells isolated from HCV-infected patients as well as FCRL-5-transfected cell lines. No cytotoxicity against T cells or conventional B cells was observed. CONCLUSION: These findings suggest that FCRL-5-targeting therapies could be a specific treatment for HCV-associated MC vasculitis and other FCRL-5-positive autoimmune B cell disorders.
23772034 Different stages of primary Sjogren's syndrome involving lymphotoxin and type 1 IFN. 2013 Jul 15 Primary Sjögren's syndrome (pSS) is a complex autoimmune disease starting in the salivary and lacrimal glands and continuing to involve the lungs and kidneys with the eventual development of lymphoma. Many studies have emphasized the role of type 1 IFN (IFN-α) and lymphotoxin α (LTα) in the pathogenesis of the disease. The present studies were designed to delineate the role of IFN-α in pSS using an animal model, the IL-14α (IL14αTG) transgenic mouse. IL14αTG mice lacking the type 1 IFNR (IL14αTG.IFNR(-/-)) had the same submandibular gland and lacrimal gland injury as did the IL14αTG mice, but they lacked the later parotid gland and lung injury. Development of lymphoma was delayed in IL14αTG.IFNR(-/-) mice. The switch from IgM to IgG autoantibodies as well as the increase in serum IgG2a seen is IL14αTG mice was inhibited in IL14αTG.IFNR(-/-) mice. Production of LTα was identified in both IL14αTG mice and IL14αTG.IFNR(-/-) mice at the time that salivary gland injury was occurring. These and previous studies suggest a model for pSS that separates the disease into several stages: 1) initial injury to the submandibular and lacrimal glands via an environmental insult and LTα; 2) amplification of local injury via the production of type 1 IFN; injury to the parotid glands, lungs, and kidneys is seen; 3) progression of systemic inflammation with the eventual development of large B cell lymphoma. Understanding these different stages will help to develop strategies for treatment of patients with pSS based on the status of their disease.